Tissue-engineered oral mucosa

Advances in tissue engineering have permitted the three-dimensional (3D) reconstruction of human oral mucosa for various in vivo and in vitro applications. Tissue-engineered oral mucosa have been further optimized in recent years for clinical applications as a suitable graft material for intra-oral and extra-oral repair and treatment of soft-tissue defects. Novel 3D in vitro models of oral diseases such as cancer, Candida, and bacterial invasion have been developed as alternatives to animal models for investigation of disease phenomena, their progression, and treatment, including evaluation of drug delivery systems. The introduction of 3D oral mucosal reconstructs has had a significant impact on the approaches to biocompatibility evaluation of dental materials and oral healthcare products as well as the study of implant-soft tissue interfaces. This review article discusses the recent advances in tissue engineering and applications of tissue-engineered human oral mucosa.     

Head‐pelvis coupling is increased during turning in patients with Parkinson's disease and freezing of gait

Turning is the most important trigger for freezing of gait (FOG). The aim of this study was to investigate the relationship between impaired head‐pelvis rotation during turning and FOG. Head, trunk, and pelvic rotation were measured at onset and throughout a 180‐degree turn in 13 freezers and 14 nonfreezers (OFF medication). We also studied 14 controls at preferred and slow speed to investigate the influence of turn velocity on axial rotation. Location and duration of FOG episodes were defined during the turn. At turning onset, head rotation preceded thorax and pelvic rotation in all groups, but this craniocaudal sequence disappeared when FOG occurred. Maximum head‐pelvis separation was significantly greater in controls, compared to freezers and nonfreezers (35.4 versus 25.7 and 27.3 degrees; P < 0.01), but this finding was speed dependent. Timing of maximum head‐pelvis separation was delayed in freezers, compared to nonfreezers and controls, irrespective of turn velocity. This delay was correlated with increased neck rigidity (R = 0.62; P = 0.02) and worsened during FOG trials. FOG occurred more often at the end of the turn, when difference in rotation velocity between head and pelvis was greatest. Even after controlling for speed and disease severity, turning in freezers was characterized by delayed head rotation and a closer coupling between head and pelvis, especially in turns where FOG occurred. These changes may be attributed to delayed preparation for the change in walking direction and, as such, contribute to FOG. © 2013 Movement Disorder Society     

Measurement of stain on extracted teeth using spectrophotometry and digital image analysis

Abstract: Aim: The aim of this study was to assess the reliability and validate a customized image analysis system, designed for use within clinical trials of general dental hygiene and whitening products, for the measurement of stain levels on extracted teeth and to compare it with reflectance spectrophotometry. Method: Twenty non‐carious extracted teeth were soaked in an artificial saliva, brushed for 1 min using an electric toothbrush and a standard toothpaste, bleached using a 5.3% hydrogen peroxide solution and cycled for 6 h daily through a tea solution. CIE L* values were obtained after each treatment step using the customized image analysis system and a reflectance spectrophotometer. A statistical analysis was carried out in SPSS. Results: Fleiss’ coefficient of reliability for intra‐operator repeatability of the image analysis system and spectrophotometry was 0.996 and 0.946 respectively. CIE L* values were consistently higher using the image analysis compared with spectrophotometry, and t‐tests for each treatment step showed significant differences (P < 0.05) for the two methods. Limits of agreement between the methods were ?27.95 to +2.07, with a 95% confidence of the difference calculated as ?14.26 to ?11.84. The combined results for all treatment steps showed a significant difference between the methods for the CIE L* values (P < 0.05). Conclusion: The image analysis system has proven to be a reliable method for assessment of changes in stain level on extracted teeth. The method has been validated against reflectance spectrophotometry. This method may be used for pilot in vitro studies/trials of oral hygiene and whitening products, before expensive in vivo tests are carried out.     

Health status, sociodemographic factors, and the use of prescribed psychotropic drugs

The relations among sociodemographic factors, health status, and use of prescribed sleeping pills and tranquilizers are examined. The data are from the Rand Health Insurance Experiment, which has a random sample of the nonaged, noninstitutionalized, civilian population in six U.S. sites. Information on sociodemographic factors, health status, and the use of prescribed psychotropic drugs during the previous 3 months was obtained from self-report questionnaires collected at enrollment. Mental and physical health status have large independent and significant effects on the probability of use of both prescribed tranquilizers (P less than 0.0001) and sleeping pills (P less than 0.0001), whether or not we remove the effects of sociodemographic factors. For the probability of tranquilizer use, there is no significant interaction between gender and mental health or between mental health and physical health. Age and gender have large and significant effects on the use of prescribed psychotropic drugs even after controlling for differences in health status and other demographic factors. The effects of site and socioeconomic status are modest compared with the effects of health, age, and gender.     

Percutaneous single- and double-balloon aortic valvotomy in adolescents and young adults with congenital aortic stenosis

Percutaneous balloon aortic valvotomy was attempted in six consecutiveadolescents and young adults, (meanage 18 ± 5 years),with severe congenital aortic valvular stenosis. Peak systolicaortic valve gradient measurement and aortography was performedbefore and immediately after valvotomy, and a 1–6 monthsfollow-up. The single-balloon technique was used in two patientsand the double-balloon technique in four patients. After balloonvalvotomy the mean peak systolic aortic valve gradient (PSG)decreased from 122 ± 53 to 43 ± 20 mmHg (P >001). The haemodynamic improvement persisted at follow-up (PSG= 47 ±31 mmHg), except in one patient who had previouslyundergone aortic surgical valvotomy. One balloon valvotomy wasunsuccessful, presumably because of the selection of an inappropriatelysmall balloon. Two patients with critical aortic stenosis (PSG>165mmHg), who exhibited a thick aortic valve on echocardiographywith a relatively small aortic root and annulus, had a dramaticreduction in PSG. However, the degree of aortic regurgitationincreased significantly in both cases. The theoretical haemodynamicadvantage of the double versus the single balloon techniqueswas confirmed in one patient. We have demonstrated that percutaneousballoon aortic valvotomy using either the single- or double-balloontechnique is feasible in young adults with severe congenitalaortic stenosis. Further studies are required both to defineappropriate patients and the selection of balloon diameter andlength.     

Appropriateness of referral of coronary angiography patients in Sweden. SECOR/SBU Project Group

OBJECTIVE: To evaluate the appropriateness of referral following coronary angiography in Sweden. DESIGN: Prospective survey and review of medical records. PATIENTS: Consecutive series of 2767 patients who underwent coronary angiography in Sweden between May 1994 and January 1995 and were considered for coronary revascularisation. MAIN OUTCOME MEASURES: Percentage of patients referred for coronary artery bypass graft surgery (CABG) and percutaneous transluminal coronary angioplasty (PTCA) for indications that were judged necessary, appropriate, uncertain, and inappropriate by a multispecialty Swedish national expert panel using the RAND/University of California Los Angeles (UCLA) appropriateness method, and the percentage of patients referred for continued medical management who met necessity criteria for revascularisation. RESULTS: Half the patients were referred for CABG, 25% for PTCA, and 25% for continued medical therapy. CABG was judged appropriate or necessary for 78% of patients, uncertain for 12% and inappropriate for 10%. For PTCA the figures were 32%, 30% and 38%, respectively. Two factors contributed to the high inappropriate rate. Many of these patients did not have "significant" coronary artery disease (although all had at least one stenosis > 50%) or they were treated with less than "optimal" medical therapy. While 96% of patients who met necessity criteria for revascularisation were appropriately referred for revascularisation, 4% were referred for continued medical therapy. CONCLUSIONS: Using the RAND/UCLA appropriateness method and the definitions agreed to by the expert panel, which may be considered conservative today, it was found that 19% of Swedish patients were referred for coronary revascularisation judged inappropriate. Since some cardiovascular procedures evolve rapidly, the proportion of patients referred for inappropriate indications today remains unknown. Nevertheless, physicians should actively identify those patients who will and will not benefit from coronary revascularisation and ensure that they are appropriately treated.